It's been a zillion years since electronics school and I've forgotten way too much basic analog theory. Any help would be greatly appreciated.

I have a small stereo amp kit that uses a TDA2004 chip to which I must add a volume control. The input is line level from a PC sound card (application is an upright videogame cabinet).

I have a 10kΩ stereo audio-taper pot. Please see attached snippet from the spec sheet for the TDA2004 chip. Could I just insert the 10k stereo pot inbetween the existing input capacitor and the chip input leg for each channel? That would be main pot legs from input to ground and wiper leg to chip input.

 

Put the pot before the capacitor. So connect your line input across the track and connect the capacitor to the slider (centre pin).

Simple!

 

JDT,
do you mean like the picture attached below? (of the circuit diagram of a similar amp - mono and using a different chip, but wiring would be theoretically similar). Won't putting the pot BEFORE the cap bleed some of the signal off to ground? If so, enough to matter?

The schematic in the pic originally had the cap before the pot, I edited it to move the cap to ensure I was correctly understanding what you meant. Thanks.

 

It works as intended. If any signal is being bled off to ground, it's inconsequential for this application. I don't fully understand why, but I'll accept that it works and thank you profusely. Now I can finally FINISH this project.

 

Note that you should use a ganged dual audio taper or log pot, rather than a linear pot.

If you have the "ends" swapped on a log/audio taper pot, you will have very little control over the volume; just change the end wires around to fix it.

 

The polarity of your input capacitor C1 is shown backwards. The input pin of the IC has a positive voltage so the (+) wire of the capacitor should go there.
The datasheet recommends 2.2uf, not 1uF so that the POP when the power is applied is not too loud.